Styling Cross-Browser Compatible Range Inputs with Sass

input-range.scss

// Styling Cross-Browser Compatible Range Inputs with Sass
// Github: https://github.com/darlanrod/input-range-sass
// Author: Darlan Rod https://github.com/darlanrod
// Version 1.4.1
// MIT License

$track-color: #eceff1 !default;
$thumb-color: #607d8b !default;

$thumb-radius: 12px !default;
$thumb-height: 24px !default;
$thumb-width: 24px !default;
$thumb-shadow-size: 4px !default;
$thumb-shadow-blur: 4px !default;
$thumb-shadow-color: rgba(0, 0, 0, .2) !default;
$thumb-border-width: 2px !default;
$thumb-border-color: #eceff1 !default;

$track-width: 100% !default;
$track-height: 8px !default;
$track-shadow-size: 1px !default;
$track-shadow-blur: 1px !default;
$track-shadow-color: rgba(0, 0, 0, .2) !default;
$track-border-width: 2px !default;
$track-border-color: #cfd8dc !default;

$track-radius: 5px !default;
$contrast: 5% !default;

@mixin shadow($shadow-size, $shadow-blur, $shadow-color) {
  box-shadow: $shadow-size $shadow-size $shadow-blur $shadow-color, 0 0 $shadow-size lighten($shadow-color, 5%);
}

@mixin track {
  cursor: pointer;
  height: $track-height;
  transition: all .2s ease;
  width: $track-width;
}

@mixin thumb {
  @include shadow($thumb-shadow-size, $thumb-shadow-blur, $thumb-shadow-color);
  background: $thumb-color;
  border: $thumb-border-width solid $thumb-border-color;
  border-radius: $thumb-radius;
  cursor: pointer;
  height: $thumb-height;
  width: $thumb-width;
}

[type='range'] {
  -webkit-appearance: none;
  margin: $thumb-height / 2 0;
  width: $track-width;

  &:focus {
    outline: 0;

    &::-webkit-slider-runnable-track {
      background: lighten($track-color, $contrast);
    }

    &::-ms-fill-lower {
      background: $track-color;
    }

    &::-ms-fill-upper {
      background: lighten($track-color, $contrast);
    }
  }

  &::-webkit-slider-runnable-track {
    @include track;
    @include shadow($track-shadow-size, $track-shadow-blur, $track-shadow-color);
    background: $track-color;
    border: $track-border-width solid $track-border-color;
    border-radius: $track-radius;
  }

  &::-webkit-slider-thumb {
    @include thumb;
    -webkit-appearance: none;
    margin-top: ((-$track-border-width * 2 + $track-height) / 2) - ($thumb-height / 2);
  }

  &::-moz-range-track {
    @include track;
    @include shadow($track-shadow-size, $track-shadow-blur, $track-shadow-color);
    background: $track-color;
    border: $track-border-width solid $track-border-color;
    border-radius: $track-radius;
  }

  &::-moz-range-thumb {
    @include thumb;
  }

  &::-ms-track {
    @include track;
    background: transparent;
    border-color: transparent;
    border-width: ($thumb-height / 2) 0;
    color: transparent;
  }

  &::-ms-fill-lower {
    @include shadow($track-shadow-size, $track-shadow-blur, $track-shadow-color);
    background: darken($track-color, $contrast);
    border: $track-border-width solid $track-border-color;
    border-radius: $track-radius * 2;
  }

  &::-ms-fill-upper {
    @include shadow($track-shadow-size, $track-shadow-blur, $track-shadow-color);
    background: $track-color;
    border: $track-border-width solid $track-border-color;
    border-radius: $track-radius * 2;
  }

  &::-ms-thumb {
    @include thumb;
    margin-top: 0;
  }
}